First off: stuff like Carapace, Vox casters and other nice accessories can be modelled without actually using them ingame, as long as you tell your opponent. I've never had a problem with that.
Command squad: get rid of Carapace, Vox Caster, bodyguards, medic and krak grenades. Most of this stuff is only useful if your guys leave their tank and get personal, which they're not meant (and not equipped) to do.
If you want a sniper CCS, get snipers, not just one. A much better build:
*************** 1 HQ ***************
Company Command Squad
- Company Commander
- 4 x Veteran with Sniper rifle
+ Chimera Transport
- Multi-laser
- Heavy bolter
- - - > 125
This squad does what you want: give orders and lend some fire support via sniper rifles and the Chimeras heavy weapons.
Veterans: Flamers are a waste of those guys BS of 4. Sure, it's possible, but not optimal in my opinion. Also, Grenadiers doctrine... oh well. Go for it if you want, I consider it to be a waste of points. It can be useful for your plasma vets though when their guns overheat. I'd propose this for the vets, grenadiers included. I'd seriously consider dropping it at least on the melta squad though:
Veteran Squad
- Grenadiers
- 3 x Veteran with Plasma gun
- Veteran Sergeant
+ Chimera Transport
- Multi-laser
- Heavy flamer
- - - > 200
Veteran Squad
- Grenadiers
- 3 x Veteran with Meltagun
- Veteran Sergeant
+ Chimera Transport
- Multi-laser
- Heavy flamer
- - - > 185
Note that those Chimeras have Heavy Flamers as hull mounted guns instead of Heavy Bolters, as you'll be using them more aggressively.
Sentinels. If you use three single ones that's three pretty easy kill points, if you use them in a squad their weapons loadout contradicts. My proposal: take a squad of three unarmored ones and scout or flank them.
Smoke launchers can be used for one turn, they prevent any shooting from you, but give you a cover save.
Soo, my proposed Sentinel squad:
3 Scout Sentinels
- 2 x Multi-laser
- 1 x Autocannon
- - - > 110
Cheap, cheerful, annyoing, expendable. Come in flanking and shoot some tank in the ass. If they survive, repeat.
If you really, really want to go for armored sentinels, I'd propose something like this:
3 Armoured Sentinels
- 3 x Lascannon
- Camo netting
- - - > 240
Too expensive for my taste, but they have a clear job, tank hunting, and they get a 3+ save when in cover. So: plop 'em into cover and blaze away. In a pinch you can engage infantry (make sure they have no powerfists or stuff like that!!) and tank them almost indefinitely.
Leman Russ: almost good, but get rid of the extra armor. Not really needed nowadays. You want that Russ as a firebase, not a cavalry tank.
Extra stuff to consider:
a small infantry platoon. For starters, one command squad, two infantry squads, a mortar squad. Something like this:
Infantry Platoon
+ Command Squad
- Platoon Commander
- 3 x Guardsman with Flamer
+ Infantry Squad
- Guardsmen Weapons Team with Autocannon
- Upgrade to Sergeant
+ Infantry Squad
- Guardsmen Weapons Team with Autocannon
- Upgrade to Sergeant
+ Heavy Weapons Squad
- 3 x Mortar team
- - - > 225
A cheapo command squad to give some orders, 3 flamers will make a dent into anything coming too close. 2 Infantry squads with autocannons, some long range fire vs. transports and some bodies. Never a bad thing. 3 Mortars. Annoying and good. Those are Gold for their points.
Hope that helped!